I was wondering if someone could let me know which one of the following self-made sentences sounds more natural in the way that it could be more understood not only by well-educated people of English language:

a) I had an outpatient surgery 1 hour ago.

b) I had a same day surgery 1 hour ago.

c) I had an ambulatory surgery 1 hour ago.

Meanwhile, I'm not sure if they are natural structurally. If so, then please let me know how a native would call fast and easy type of surgeries?

P.S. I think they are very scientific terms which are rarely used in everyday conversations to indicate what I'm going to say.

In AmE, surgery in this locution is understood to be a process, whereas the operation is that which is accomplished during the surgical process.

Of the two, operation is the more colloquial. Since you ask about those who are not well-educated: there are some speakers of American English who have had little experience of hospitals for a variety of social, economic, and political reasons, and speakers who are marginally literate, and a person who falls into both groups might not use the word outpatient and certainly not the word ambulatory. They might express the idea with a circumlocution:

He had an operation this morning, the kind where you are in and out in an hour.

He had an operation this morning, the kind where you can go home right afterwards.

He had an operation this morning, the kind where you can go home the same day.

He had an operation this morning, but not the kind where you have to stay in the hospital overnight.